From mboxrd@z Thu Jan  1 00:00:00 1970
From: "Clemens Ladisch" <cladisch@fastmail.net>
Subject: Re: about sound/core/pcm_lib.c:1997: capture read
 error (DMA or IRQ trouble?)
Date: Wed, 26 Sep 2007 08:24:20 +0200
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To: Akio <akioolin@gmail.com>, alsa-devel@alsa-project.org
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Akio write:
> after long time amr-wb codec loopback test. (above 90 hours)
> I got the following kernel message.  it comes from snd_pcm_lib_read1()
> function. 
> ALSA sound/core/pcm_lib.c:1997: capture read error (DMA or IRQ trouble?)

This error indicates that no interrupt has been received for ten
seconds.

I would have guessed that some 32-bit counter has overflowed, but at
48 kHz, a frame counter would overflow after slightly less than
25 hours.


HTH
Clemens